In a double-blind, randomised study in which hypertensive men drank one cup of black tea daily, both systolic and diastolic blood pressure were reduced.

The blood pressure-lowering effect was maintained even after a large intake of fatty, sugary food, which usually constricts blood vessels, showing that ''cardiovascular protection can be achieved even without much sacrifice and with normal intakes'', Claudio Ferri, a professor at Italy's University of L'Aquila School of Internal Medicine and co-author of the study, said.

Healthier blood vessels create better blood flow, which means all of your organs, including the brain, are receiving more blood, oxygen and nutrients, enhancing your body's ability to fight disease. So healthier blood vessel linings might be one reason why tea consumption seems associated with so many benefits.

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It improves bone health. After drinking four to six cups of green tea daily for six months, post-menopausal women with low bone mass (osteopaenia) achieved an improvement in certain short-term measures of bone health in a National Institutes of Health-funded study conducted at Texas Tech University Health Sciences Centre. They also improved muscular strength. Tea reduced oxidative stress and inflammation, preventing the usual bone and muscle breakdown.

It can help your thinking. When your brain receives better blood flow and oxygen, and inflammation and oxidative stress are reduced, there is improved cognitive function, according to studies.

It might reduce cancer risk. Many animal and test-tube studies have found anti-cancer effects of tea, but human studies have been less consistent. ''In lab studies, compounds in tea show a lot of cancer fighting promise. Many act as antioxidants, slow tumour growth and even increase cancer cell death,'' Alice Bender of the American Institute for Cancer Research said. ''But the evidence is too limited and inconsistent to make any conclusions about tea and cancer risk for humans.''

It can help you lose weight. Not only does tea have fewer calories than most beverages (zero without milk and sugar) but certain compounds in tea, and especially green tea, have been found to burn body fat. Caffeine slightly increases fat-burning, but recent studies show ''the combination of caffeine and green tea catechins [tea's antioxidants] is even more effective at increasing energy expenditure and fat oxidation, though the effect is small, burning 100 calories over 24 hours, or a loss of 2.8 pounds [1.27 kilos] over 12 weeks'', Rick Hursel of Maastricht University, co-author of one study, said.

It can help you de-stress. An amino acid called L-theanine, in combination with caffeine, might reduce stress. Several studies have shown this combination, which occurs naturally in tea, reduces cortisol, the stress hormone, while improving mental alertness.